Rotary Valve for Industrial Fluid Flow Control

Abstract

A cylindrical rotary valve to control or affect fluid flow in processes where the fluid temperature must be maintained within a target range, the fluid pressure is varied and / or the amount of fluid flow is controlled comprising one or more of the following elements alone or in combination: (i) the use of a temperature control core in the valve shaft, (ii) the contoured or tapered shapes or the conduits (iii) the use of the valve to create predictable pulses or waves in the fluid being controlled, (iv) a modular system of valves where the valve body is fixed and the valve shaft is replaceable with a second valve shaft of different conduit shape, (v) a rotary valve with multiple inputs or multiple outputs for either mixing or diverting of input fluids, and (vi) the use of the valve in abrasive particulate blasting and in particular dry ice blasting.

Description

FIELD OF THE INVENTION[0001]The present invention relates to a rotary valve with a cylindrical valve shaft and valve housing to control or affect fluid flow, also to control or affect fluid flow in processes where the fluid temperature must be maintained within a target range, the fluid pressure is varied and / or the amount of fluid flow is controlled.BACKGROUND OF THE INVENTION[0002]Valves are a well known part of industrial, research and residential fluid flow processes, where the valve either inhibits (e.g, in the case of a stop valve), regulates (e.g., in the case of a check valve) or affects (e.g. in creating or dampening pressure pulses in the fluid) the flow of fluid in a system. Between the input and output directions of the valve, the shape and seal of the valve gate determines many of the functions and properties of the valve.[0003]Prior industrial applications requiring fluid flow control have typically depended on either poppet, spool, butterfly or ball valves to either c...

AI Technical Summary

Benefits of technology

[0017]The thermally conductive fluid is used to either cool or heat the valve shaft, so as to control the thermal expansion or contraction of the valve or to achieve a particular thermodynamic effect in the fluid whose flow is being controlled. Since the valve shaft is cylindrical in shape, and not spherical, the unmodified outer surface of the cylindrical valve shaft can be at a constant distance from an axial temperature control bore. This allows for substantially reliable and even heat transfer and temperature control along the length of the valve shaft.

[0034]Various valve embodiments of the present invention produce one or more advantages over current valving systems typically used in the prior art. By way of example, the simplified construction of the rotary valve (one piece) allows for improved heat distribution throughout the valve, which is not easily achieved in valves where each valve is machined separately and fitted over a valve shaft; the wave valve has particular uses in applications where fluid pressure and volume must be varied continually in a system without entirely stopping flow; the modular design allows for ease of replacement and therefore ease of modification of entire processes by replacing only the valve shaft. In certain aspects, valves can be pre heated at process start up to ensure proper functioning of the valve and the correct temperature can be maintained during the process to prevent either excessive thermal expansion or compression and related valve jamming or leakage.

Problems solved by technology

In either case, flow is controlled by rotating the valve gate through a sufficient number of degrees (typically 90°) so that the passage no longer provides fluid communication between the input and output ports of the valve housing.

Consequently, mounting the multiple valve gates results in a less efficient seal compared to a single ball valve.

Spherical valves, or indeed any valves, mounted on a shaft have known heat transfer limitations and mechanical limitations at the point of connection between the parts.

As the temperature of the valve fluctuates, the fit is distorted between the sealing material and valve shaft.

To date, the compressed air has been provided in a continuous stream to the dry ice creating pressure build up, noise, ice loss and air loss.

The noise in these devices is sufficient to present occupational health and safety concerns.

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